A great number of data islands may exist in the big data era. For example, the data of a person can be dispersedly stored with different enterprises. However, there may be no complete mutual trust among the enterprises due to competitive relationships and concerns of the user privacy protection, which may create a barrier for cooperation of data statistics among the enterprises. There is an urgent need for a solution on how to achieve some data statistics calculations using the data owned by different parties without leaking data privacy of the respective enterprises, to ensure that the privacy of the core data of the respective enterprises is fully protected. However, no good solution is available so far.